Children who live in regions of higher airborne pollution have slower lung growth and diminished lung function, according to a study published in the New England Journal of Medicine.

It tracked about 2,000 children in southern California for eight years, making it the longest and largest study of its kind. The children's lungs were tested annually between the ages of 10 and 18, when the lungs grow to full capacity.

As the children in the study grew to become teenagers, doctors found evidence of lung damage in those who didn't smoke or have prior lung problems such as asthma.

According to the study, eight per cent of 18-year-olds had lung capacity less than 80 per cent of normal, compared with about 1.5 per cent of teens in communities with the least pollution.

David Bates, a scientist from the University of British Columbia who worked on the study, says the results are important.

"It's a warning that the present city environment...is affecting their long-term health," said Bates.

Scientists had expected to find that ozone was the main culprit in problems with lung development.

However, the study showed that primary pollutants, like industrial smokestacks and vehicle exhaust, harm children's lungs the most.

While the study was done in California, where there are more cars and factories, an environmental group says the findings can be applied to parts of Canada.

"If you consider climate change and the impact it has on the air pollution levels in Toronto and Windsor and even downwind in Atlantic Canada, what we're seeing in California today may be the type of conditions that we find here in the next 20 to 30 years," said Quentin Chiotti, with Pollution Probe.

Health Canada is planning its own study in January to confirm the link between primary pollutants and lung development. It's planning to study 25,000 children, including hundreds in Windsor, Ont., who will wear backpacks fitted with portable monitors.